With the increasing penetration of distributed energy resources

the strength of AC power systems has progressively declined. In weak AC systems

the equivalent grid impedance rises

intensifying interactions between converters and the power grid. Traditional unbalanced control strategies exhibit reduced effectiveness in suppressing twice fundamental frequency power ripples and may even exacerbate transient power oscillations under disturbances. To address this issue

this paper first quantitatively analyzes the limitations of conventional unbalanced control strategies in mitigating power ripples within weak AC systems. Subsequently

a interactive power transfer model is established

incorporating dynamic characteristics of converter control loop

the phase locked loop (PLL)

and the transmission line. Furthermore

a composite control-based unbalanced control strategy-dynamic power feed forward compensation (DPFC) is proposed for weak grid applications. By equivalently compensating the oscillatory power generated from closed-loop system interactions into the inverter's power outer loop

the proposed strategy effectively suppresses power ripples during both transient and steady-state operations. Finally

the effectiveness and superiority of the proposed strategy are verified by CHIL and PHIL experiments.